PHOENIX — The Phoenix Mercury have fired Corey Gaines as head coach and general manager and named former Grand Canyon University coach Russ Pennell as interim coach.

Amber Cox, Mercury president and chief operating officer, will take over as interim general manager.

"First and foremost, we thank Corey for his years of dedication to this franchise, its players and its fans," Cox said in a statement. "Corey helped bring two championships to our organization and for that we will be forever grateful. Unfortunately, our team's performance this season has not lived up to our expectations, and at this time, a change was necessary. Russ Pennell is a proven leader and winner, whose resume speaks to his ability to build a winning culture founded in discipline and fundamentals."

The Mercury are 10-11 under Gaines this season and 7½ games behind West-leading Minnesota.

Gaines joined the team in 2006 as an assistant coach and took over as head coach in 2008, leading the Mercury to its second title in 2009. He's the longest serving Mercury coach at nearly six years and the winningest, with 90 regular season victories and 11 playoff victories.

Pennell has more than 30 years of experience, including coaching stints at Arizona State University, the University of Arizona and most recently Grand Canyon University.

At Grand Canyon, Pennell went 72-44 over four years. He rebuilt the program and brought the team to two straight NCAA Division II tournament appearances.